I think the /usr/bin/python executable you’re seeing is the Apple-supplied one.
Here’s what I have in /usr/bin, which is all from Apple:
$ ls -l /usr/bin/pyth*
-rwxr-xr-x 1 root wheel 66576 Apr 29 02:29 /usr/bin/python
-rwxr-xr-x 5 root wheel925 Jul 31 2016 /usr/bin/python-config
lrwxr-
I’m new to Python. I seem to have three partially installed Pythons on my Mac
Sierra.
One from Apple
One from Homebrew
And one from the Python Mac installer
In particular, for example, I have a python executable in /usr/bin:
$ which python
/usr/bin/python
This is an actual executable not a sym